Publications by authors named "Huimin Wu"

64 Publications

Native American Patients with Chronic Obstructive Pulmonary Disease Exacerbations in a Tertiary Academic Medical Center - A Pilot Study.

Int J Chron Obstruct Pulmon Dis 2021 28;16:1163-1170. Epub 2021 Apr 28.

Pulmonary, Critical Care and Sleep Medicine, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.

Purpose: The prevalence of chronic obstructive pulmonary disease (COPD) and comorbidities (eg diabetes and obesity) among Native American (NA) population are higher than among the general US population. However, studies of COPD in NAs are scarce. Oklahoma has the largest NA population affiliated with federally recognized tribes in the country and is an ideal location for such research. A pilot study was designed to investigate the characteristics of NA patients with COPD exacerbations in a tertiary academic medical center.

Patients And Methods: We conducted a retrospective exploratory study of NA adults with COPD exacerbation hospitalizations and/or emergency department visits at the University of Oklahoma Medical Center between July 2001 and June 2020. Medical records were reviewed to confirm COPD exacerbation and outcomes, including death, mechanical ventilation, intensive care unit (ICU) stay, home oxygen, and 30-day readmission. Additional collected data included socio-demographics, body mass index, diabetes, other COPD comorbidities and clinical variables.

Results: Of 630 encounters reviewed, 159 met the inclusion criteria, representing 91 patients. Most patients were female (64%), obese or overweight (68%), and had diabetes (42%) or hypertension (71%). Mean age was 60 years old, but women were 5 years younger than men. Among the 76 patients with COPD hospitalizations, 31 patients (41%) had an intensive care unit (ICU) stay and 19 (25%) were intubated in their last hospitalization. Among 9 patients (10%) with 30-day readmissions, 8 were female. Medicare, Indian Health Service, Tribal health service, or Medicaid were the most frequently used payment sources. Sex, diabetes, and obesity were not associated with hospital length of stay, 30-day readmission or supplemental O2 use.

Conclusion: Hospitalized NA COPD patients at this tertiary care center had multiple comorbidities. Many required ICU care and intubation. Larger studies of the risk and mitigating factors for COPD health outcomes in NA patients are needed.
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http://dx.doi.org/10.2147/COPD.S299178DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8089083PMC
April 2021

Enhanced the photoelectrochemical performance of BiXO (X = W, Mo) for detecting hexavalent chromium by modification of CuS.

J Environ Sci (China) 2021 May 16;103:185-195. Epub 2020 Nov 16.

Health Assessment Center, Zhejiang Provincial Key Laboratory of Watershed Science and Health, College of Public Health and Management, University Town, Chashan, Wenzhou Medical University, Wenzhou 325035, China. Electronic address:

In this work, BiXO (X = W, Mo) are synthesized at different temperatures. The results of tests find the optimal temperatures of BiWO and BiMoO are 180 and 160°C (BW-180, BM-160). Then, BW-180 and BM-160 are further compounded with different contents of CuS. The results of photoelectrochemical (PEC) tests show that CuS can improve the PEC performance of semiconductor materials, and it has better performance when CuS mass fraction is 5%. These maybe the photoelectron potentials generated by CuS/BiXO (X = Mo, W) heterojunction reduce the combination of photogenerated electrons and holes. When the PEC sensor based on 5%-CuS/BW-180 detects Cr(VI), it has a linear range of 1-80 μmol/L with detection limit of 0.95 μmol/L, while the PEC sensor based on 5%-CuS/BM-160 detects Cr(VI) has a linear range of 0.5-230 μmol/L and a detection limit of 0.12 μmol/L. Thus, 5%-CuS/BiXO has potential application in hexavalent chromium detection.
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http://dx.doi.org/10.1016/j.jes.2020.10.019DOI Listing
May 2021

Host-Guest Interaction-Mediated Photo/Temperature Dual-Controlled Antibacterial Surfaces.

ACS Appl Mater Interfaces 2021 Mar 18;13(12):14543-14551. Epub 2021 Mar 18.

College of Materials Science & Engineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China.

Development of smart switchable surfaces to solve the inevitable bacteria attachment and colonization has attracted much attention; however, it proves very challenging to achieve on-demand regeneration for noncontaminated surfaces. We herein report a smart, host-guest interaction-mediated photo/temperature dual-controlled antibacterial surface, topologically combining stimuli-responsive polymers with nanobactericide. From the point of view of long-chain polymer design, the peculiar hydration layer generated by hydrophilic poly(2-hydroxyethyl methacrylate) (polyHEMA) segments severs the route of initial bacterial attachment and subsequent proliferation, while the synergistic effect on chain conformation transformation poly(-isopropylacrylamide) (polyNIPAM) and guest complex dissociation azobenzene/cyclodextrin (Azo/CD) complex greatly promotes the on-demand bacterial release in response to the switch of temperature and UV light. Therefore, the resulting surface exhibits triple successive antimicrobial functions simultaneously: (i) resists ∼84.9% of initial bacterial attachment, (ii) kills ∼93.2% of inevitable bacteria attack, and (iii) releases over 94.9% of killed bacteria even after three cycles. The detailed results not only present a potential and promising strategy to develop renewable antibacterial surfaces with successive antimicrobial functions but also contribute a new antimicrobial platform to biomedical or surgical applications.
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http://dx.doi.org/10.1021/acsami.0c21626DOI Listing
March 2021

Fluorescent and visual assay of HO and glucose based on a highly sensitive copper nanoclusters-Ce(III) fluoroprobe.

Anal Bioanal Chem 2021 Mar 28;413(8):2135-2146. Epub 2021 Jan 28.

Center for Health Assessment, Zhejiang Provincial Key Laboratory of Watershed Science and Health, College of Public Health and Management, Wenzhou Medical University, Zhejiang, 325035, Wenzhou, China.

Herein, we synthesized and characterized glutathione-capped copper nanoclusters (CuNCs) using a convenient one-pot chemical reduction approach based on glutathione as capping and reducing agents. The Ce(III) induced aggregation-induced emission of CuNCs to form a CuNCs-Ce fluoroprobe due to electrostatic and coordination interactions between Ce and CuNCs. In contrast to CuNCs, the fluorescent intensities (FLs) of CuNCs-Ce were enhanced by ~ 40-fold concomitant with 20-nm blue-shift of the maximum emission, and a 3.45-fold lengthening of the average fluorescent lifetime. The FLs of CuNCs-Ce were selectively quenched at 650 nm by hydrogen peroxide (HO) via the redox reaction. Based on this phenomenon, the sensitive assay of HO was realized, and the linear range spanned over the range of 14-140 μM. Notably, the visualization of the fluorescence quenched effect of HO could be easily attained. Additionally, glucose could be specifically oxidized by glucose oxidase to produce HO, and thus the detection of glucose was achieved according to changes in the concentrations of HO. Under optimized conditions, the fluorescent assay of glucose based on the CuNCs-Ce system offered the linear range of 8-48 μM with detection limit of 2.4 μM. Meanwhile, high selectivity of the as-constructed fluorescent assay allows the sensitive detection of HO and glucose in real-world care products and human serum samples, showing a great application potential in their conventional monitoring.
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http://dx.doi.org/10.1007/s00216-021-03181-2DOI Listing
March 2021

Capillary-driven blood separation and in-situ electrochemical detection based on 3D conductive gradient hollow fiber membrane.

Biosens Bioelectron 2021 Jan 14;171:112722. Epub 2020 Oct 14.

Key Laboratory of Macromolecular Synthesis and Functionalization, ERC of Membrane and Water Treatment (MOE), Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China. Electronic address:

It is essential to develop portable, versatile, and reliable diagnostic devices in point-of-care testing (POCT). The detection of biomarkers requires selective separation and large specific surface for high sensitivity and accuracy at trace levels in whole blood samples using POCT devices. Herein, a kind of 3D electrochemical biosensors were designed via in-situ synthesizing polyaniline (PANI) and platinum nanoparticles (Pt NPs) on polysulfone hollow fiber membrane (HFM) scaffolds with gradient porous structure. The gradient porous HFMs scaffolds provide uniform capillary flow, self-driven blood separation and sufficient enzyme immobilization sites. Simultaneously, the in-situ deposited materials fulfill interconnected conductive networks, thus ensuring accurate and rapid detection of the sensors without hindering capillary progress. These sensors display ultralow sampling (~3 μL), fast fluid flow (>1 μL/ms), wide linear range (glucose: 0-24 mM, R=0.992; cholesterol: 0-9 mM, R=0.999), high sensitivity and accuracy especially under different hematocrits in POCT applications towards glucose and cholesterol. The innovative integration of POCT biosensors with interconnected conductive nanoparticles, selective blood separation and gradient porous structures can find wide application in resource-limited regions, large population screening, and public health emergencies.
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http://dx.doi.org/10.1016/j.bios.2020.112722DOI Listing
January 2021

Pharmacology, toxicity and pharmacokinetics of acetylshikonin: a review.

Pharm Biol 2020 Dec;58(1):950-958

School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China.

Context: Acetylshikonin, a naphthoquinone derivative, is mainly extracted from some species of the family Boraginaceae, such as Sieb. et Zucc., (Royle) Johnst., and Bunge. As a bioactive compound, acetylshikonin has attracted much attention because of its broad pharmacological properties.

Objective: This review provides a comprehensive summary of the pharmacology, toxicity, and pharmacokinetics of acetylshikonin focussing on its mechanisms on the basis of currently available literature.

Methods: The information of acetylshikonin from 1977 to 2020 was collected using major databases including Elsevier, Scholar, PubMed, Springer, Web of Science, and CNKI. Acetylshikonin, pharmacology, toxicity, pharmacokinetics, and naphthoquinone derivative were used as key words.

Results: According to emerging evidence, acetylshikonin exerts a wide spectrum of pharmacological effects such as anticancer, anti-inflammatory, lipid-regulatory, antidiabetic, antibacterial, antifungal, antioxidative, neuroprotective, and antiviral properties. However, only a few studies have reported the adverse effects of acetylshikonin, with respect to reproductive toxicity and genotoxicity. Pharmacokinetic studies demonstrate that acetylshikonin is associated with a wide distribution and poor absorption.

Conclusions: Although experimental data supports the beneficial effects of this compound, acetylshikonin cannot be considered as a therapy drug without further investigations, especially, on the toxicity and pharmacokinetics.
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http://dx.doi.org/10.1080/13880209.2020.1818793DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7534356PMC
December 2020

SIDT1-dependent absorption in the stomach mediates host uptake of dietary and orally administered microRNAs.

Cell Res 2021 Mar 17;31(3):247-258. Epub 2020 Aug 17.

Nanjing Drum Tower Hospital Center of Molecular Diagnostic and Therapy, State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute of Life Sciences (NAILS), NJU Institute of AI Biomedicine and Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, China.

Dietary microRNAs have been shown to be absorbed by mammals and regulate host gene expression, but the absorption mechanism remains unknown. Here, we show that SIDT1 expressed on gastric pit cells in the stomach is required for the absorption of dietary microRNAs. SIDT1-deficient mice show reduced basal levels and impaired dynamic absorption of dietary microRNAs. Notably, we identified the stomach as the primary site for dietary microRNA absorption, which is dramatically attenuated in the stomachs of SIDT1-deficient mice. Mechanistic analyses revealed that the uptake of exogenous microRNAs by gastric pit cells is SIDT1 and low-pH dependent. Furthermore, oral administration of plant-derived miR2911 retards liver fibrosis, and this protective effect was abolished in SIDT1-deficient mice. Our findings reveal a major mechanism underlying the absorption of dietary microRNAs, uncover an unexpected role of the stomach and shed light on developing small RNA therapeutics by oral delivery.
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http://dx.doi.org/10.1038/s41422-020-0389-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8026584PMC
March 2021

Simultaneous determination of heavy metals by an electrochemical method based on a nanocomposite consisting of fluorinated graphene and gold nanocage.

Mikrochim Acta 2020 06 29;187(7):414. Epub 2020 Jun 29.

Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, 430062, China.

Fluorinated graphene/gold nanocage (FGP/AuNC) nanocomposite was developed for simultaneous determination of heavy metals using square wave anodic stripping voltammetry. Under optimized conditions, with a buffer pH of 5.0, a deposition potential of - 1.25 V, and a deposition time of 140 s, the method can obtain the best results. The FGP/AuNC electrode exhibits low limits of detection (0.08, 0.09, 0.05, 0.19, 0.01 μg L), wide linear ranges (6-7000, 4-6000, 6-5000, 4-4000, 6-5000 μg L), and well-separated stripping peaks (at - 1.10, - 0.77, - 0.50, - 0.01, 0.31 V vs Ag/AgCl) towards Zn, Cd, Pb, Cu, and Hg, respectively. Furthermore, the FGP/AuNC electrode is also used for simultaneous determination of Zn, Cd, Pb, Cu, and Hg in real samples (peanut, rape bolt, and tea). Highly consistent results are found between the electrochemical method and atomic fluorescence spectrometry/inductively coupled plasma-mass spectrometry. The method has been successfully applied to the determination of heavy metal ions in agricultural food. Graphical abstract Schematic representation of simultaneous determination of heavy metal ions by electrochemical method. The FGP/AuNC (fluorinated graphene/gold nanocage) electrode is used to simultaneous determination of Zn, Cd, Pb, Cu, and Hg by square wave anode stripping voltammetry.
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http://dx.doi.org/10.1007/s00604-020-04393-6DOI Listing
June 2020

Study on the potential effective ingredients of Xiaosheng prescription for dry eye disease.

Biomed Pharmacother 2020 Jul 16;127:110051. Epub 2020 May 16.

School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 102488, China; Beijing Research Institute of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China. Electronic address:

Xiaosheng prescription (XSP) has been used for dry eye disease (DED) for more than 10 years in Eye Hospital of China Academy of Chinese Medicine Sciences. However, the effective ingredients involved have remained unclear, which was investigated in this study by the correlation of ingredient and therapeutic activity. Human corneal epithelial cells (HCEC) cultured with 110 mM NaCl solution in vitro and C57BL/6 mice injected subcutaneously with scopolamine hydrobromide were used to establish dry eye models, and the therapeutic effect of XSP extract 1 was better than that of XSP extract 2 significantly. Then, UPLC-Q-TOF/MS and data analysis program Progenesis QI and Makerlynx XS were used to analyze the potential effective ingredients of XSP, and 4 compounds were speculated and identified, in which Schisandrin and 1 μM of Schisantherin A could obviously increase the cell survival rate of injured cells on the cell model. It can be indicated that Schisandrin and Schisantherin A are probably the potential effective ingredients in XSP for DED.
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http://dx.doi.org/10.1016/j.biopha.2020.110051DOI Listing
July 2020

Three-Dimensional Microporous Hollow Fiber Membrane Microfluidic Device Integrated with Selective Separation and Capillary Self-Driven for Point-of-Care Testing.

Anal Chem 2020 05 16;92(9):6358-6365. Epub 2020 Apr 16.

MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.

The novel 3D microfluidic concept of "lab-on-hollow fiber membrane (HFM)" was presented for multifunctional and rapid biological assays, integrating sample size sieving and colorimetric quantification in an HFM. Herein, microporous HFMs with a gradient pore size and high hydrophilic flux were used as microfluidic device substrates. The membrane pores selectively trapped macromolecules within the inner surface, while allowing free diffusion of smaller molecules, including glucose and protein. The microfluidic flow rate in HFM closely followed the Lucas-Washburn and Laplace's models, indicating that the microfluidics facilitated the upward flow of the fluid by microcapillary action without external pumping. Subsequently, for sensing of different biomolecules, a highly sensitive fluorescent or optical chromogenic reagent was immobilized in HFM by an electrostatic interaction. Pyronin G fluorescence reagent was quenched by blood glucose, and the quenching efficiency showed a good linear correlation with glucose concentration (1-22 mM, = 0.997). Moreover, this sensing platform was then further applied for the analysis of urine protein or glucose in the visible spectrum, with a wide testing range. Compared to traditional 2D flat membrane devices, this 3D-HFM microfluidic device exhibited excellent sensing versatility and color rendering uniformity with enhanced sensitivity. Target molecules screening, conditioning, enzymatic recognition, and signal readout of biomolecules have all been implemented on this device, which has paved the way to highly sensitive assays on point-of-care testing (POCT).
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http://dx.doi.org/10.1021/acs.analchem.9b05342DOI Listing
May 2020

Effectiveness of Qingre Lishi Yishen decoction on the glomerular fibrosis of immunoglobulin A nephropathy in a rat's model.

J Tradit Chin Med 2019 08;39(4):516-523

Department of Traditional Chinese Medicine, Beijing Children' s Hospital, Capital Medical University, National Center for Children's health, Beijing 100045, China.

Objective: To investigate the effect of the clinical effective prescription of Qingre Lishi Yishen decoction (QRLS) on the activation of mesangial cells in immunoglobulin A nephropathy (IgAN) rats.

Methods: IgAN rat's model was established by combine with intragastric administration of bovine serum albumin (BSA) + intravenous injection of lipopolysaccharide (LPS) by + subcutaneous injection of carbon tetrachloride (CCL4). Then the animals were randomly divided into four groups: control group, IgAN model group, IgAN model with Valsartan (Val) treatment group and IgAN model with QRLS treatment group. To observe the indexes of 24-h urine protein, renal function, deposition of immune complexes, expression of activation factor, fibrosis marker and inflammatory cytokines in four different groups.

Results: The Val or QRLS treatment group: (a) it reduced the immune complexes deposition of IgA in glomerular mesangial and inhibited mesangial cell proliferation; (b) it decreased the expression of smooth muscle actin (α-SMA), fibronectin (FN) and tumor necrosis factor alpha (TNF-α).

Conclusion: The study suggested that QRLS ameliorate renal structure and function in IgAN rat's model. Furthermore, we also observed that QRLS alleviated mesangial cells activation and matrix accumulation partly by decreasing the α-SMA, then to downregu.
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August 2019

Synthesis and Electrochemical Properties of BiMoO/Carbon Anode for Lithium-Ion Battery Application.

Materials (Basel) 2020 Mar 4;13(5). Epub 2020 Mar 4.

Depatment of Chemical and Process Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH, UK.

High capacity electrode materials are the key for high energy density Li-ion batteries (LIB) to meet the requirement of the increased driving range of electric vehicles. Here we report the synthesis of a novel anode material, BiMoO/palm-carbon composite, via a simple hydrothermal method. The composite shows higher reversible capacity and better cycling performance, compared to pure BiMoO. In 0-3 V, a potential window of 100 mA/g current density, the LIB cells based on BiMoO/palm-carbon composite show retention reversible capacity of 664 mAh·g after 200 cycles. Electrochemical testing and density functional theory calculations are used to study the fundamental mechanism of Li ion incorporation into the materials. These studies confirm that Li ions incorporate into BiMoO via insertion to the interstitial sites in the MoO-layer, and the presence of palm-carbon improves the electronic conductivity, and thus enhanced the performance of the composite materials.
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http://dx.doi.org/10.3390/ma13051132DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7085012PMC
March 2020

A novel electrochemical sensing platform for detection of dopamine based on gold nanobipyramid/multi-walled carbon nanotube hybrids.

Anal Bioanal Chem 2020 Apr 15;412(11):2433-2441. Epub 2020 Feb 15.

Health Assessment Center, Zhejiang Provincial Key Laboratory of Watershed Science and Health, College of Public Health and Management, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.

Dopamine homeostasis is an important clinical diagnostic index, because an abnormal level in the human body is closely related to certain serious diseases. Herein, a novel electrochemical sensing platform based on gold nanobipyramid/multi-walled carbon nanotube hybrids (AuNBP/MWCNTs) is developed to detect dopamine in human fluids. Using field emission scanning electron microscopy, it is observed that AuNBPs of about 60 nm with two pyramids are well dispersed on the surface of MWCNTs. Energy-dispersive X-ray spectrometry, X-ray diffraction and X-ray photoelectron spectroscopy confirm that AuNBPs are self-assembled onto the surface of MWCNTs to form the hybrids. Cyclic voltammetry reveals that the AuNBP/MWCNTs exhibit good electrocatalytic activity toward dopamine oxidation owing to the synergistic effects of AuNBPs and MWCNTs. In addition, both cyclic voltammetry and differential pulse voltammetry display three well-resolved and distinct oxidation peaks on the AuNBP/MWCNT-modified glassy carbon electrode. Based on AuNBP/MWCNTs, the newly developed electrochemical sensor is used to detect dopamine in the presence of ascorbic acid and uric acid over a wide linear range from 50 nM to 2.7 mM and a low detection limit of 15 nM (at S/N = 3). The electrochemical sensor can also be applied for the quantitative analysis of dopamine in real samples. Graphical abstract A novel electrochemical sensing platform based on gold nanobipyramid/multi-walled carbon nanotube hybrids (AuNBP/MWCNTs) was proposed to detect dopamine in the presence of ascorbic acid and uric acid.
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http://dx.doi.org/10.1007/s00216-020-02455-5DOI Listing
April 2020

A Novel Gel-Forming Solution Based on PEG-DSPE/Solutol HS 15 Mixed Micelles and Gellan Gum for Ophthalmic Delivery of Curcumin.

Molecules 2019 Dec 24;25(1). Epub 2019 Dec 24.

School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China.

Curcumin (Cur) is a naturally hydrophobic polyphenol with potential pharmacological properties. However, the poor aqueous solubility and low bioavailability of curcumin limits its ocular administration. Thus, the aim of this study was to prepare a mixed micelle in situ gelling system of curcumin (Cur-MM-ISG) for ophthalmic drug delivery. The curcumin mixed micelles (Cur-MMs) were prepared via the solvent evaporation method, after which they were incorporated into gellan gum gels. Characterization tests showed that Cur-MMs were small in size and spherical in shape, with a low critical micelle concentration. Compared with free curcumin, Cur-MMs improved the solubility and stability of curcumin significantly. The ex vivo penetration study revealed that Cur-MMs could penetrate the rabbit cornea more efficiently than the free curcumin. After dispersing the micelles in the gellan gum solution at a ratio of 1:1 (/), a transparent Cur-MM-ISG with the characteristics of a pseudoplastic fluid was formed. No obvious irritations were observed in the rabbit eyes after ocular instillation of Cur-MM-ISG. Moreover, Cur-MM-ISG showed a longer retention time on the corneal surface when compared to Cur-MMs using the fluorescein sodium labeling method. These findings indicate that biocompatible Cur-MM-ISG has great potential in ophthalmic drug therapy.
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http://dx.doi.org/10.3390/molecules25010081DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6983186PMC
December 2019

Low-Cost NiP/NiS Heterostructured Bifunctional Electrocatalyst toward Highly Efficient Overall Urea-Water Electrolysis.

ACS Appl Mater Interfaces 2020 Jan 2;12(2):2225-2233. Epub 2020 Jan 2.

School of Chemistry, Physics and Mechanical Engineering , Queensland University of Technology (QUT) , 2 George Street , Brisbane , QLD 4000 , Australia.

Water splitting is a sustainable approach for production of hydrogen to fuel some clean energy technologies. This process, unfortunately, has been significantly impeded by the puzzles in either the efficient but economically unaffordable noble-metal-based catalysts or the low-cost but kinetically sluggish abundant-element-based catalysts. Particularly, the discovery of efficient bifunctional catalysts that can simultaneously trigger the reactions of both anode and cathode for overall water splitting still remains as a grand challenge. Herein, a novel low-cost bifunctional NiP/NiS heterostructured electrocatalyst, which is active for both the urea oxidation reaction at the anode and the hydrogen evolution reaction at the cathode, is innovated for high-efficiency overall splitting of urea-rich wastewater. A systematic configuration of a Ni foam (NF)-supported NiP/NiS catalyst electrode exhibits superior catalytic activity and stability. The NiP/NiS/NF||NiP/NiS/NF cell needs only 1.453 V to reach a current density of 100 mA/cm in basic urea-containing water, while it is 1.693 V for a reference noble-based Pt/C/NF||IrO/NF electrolysis cell. This work therefore not only contributes to develop a low-cost, high-efficiency, bifunctional electrocatalyst but also provides a practically feasible approach for urea-rich wastewater treatment.
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http://dx.doi.org/10.1021/acsami.9b14350DOI Listing
January 2020

Sample Balancing for Deep Learning-Based Visual Recognition.

IEEE Trans Neural Netw Learn Syst 2020 10 13;31(10):3962-3976. Epub 2019 Nov 13.

Sample balancing includes sample selection and sample reweighting. Sample selection aims to remove some bad samples that may lead to bad local optima. Sample reweighting aims to assign optimal weights to samples to improve performance. In this article, we integrate a sample selection method based on self-paced learning into deep learning frameworks and study the influence of different sample selection strategies on training deep networks. In addition, most of the existing sample reweighting methods mainly take per-class sample number as a metric, which does not fully consider sample qualities. To improve the performance, we propose a novel metric based on the multiview semantic encoders to reweight the samples more appropriately. Then, we propose an optimization mechanism to embed sample weights into loss functions of deep networks, which can be trained in end-to-end manners. We conduct experiments on the CIFAR data set and the ImageNet data set. The experimental results demonstrate that our proposed sample balancing method can improve the performances of deep learning methods in several visual recognition tasks.
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http://dx.doi.org/10.1109/TNNLS.2019.2947789DOI Listing
October 2020

Synthesis of Ni/NiO@MIL-101(Cr) Composite as Novel Anode for Lithium-Ion Battery Application.

J Nanosci Nanotechnol 2019 Dec;19(12):8063-8070

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials and Ministry of Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules, Hubei University, Wuhan, 430062, China.

The poor conductivity is one of the prime reasons restricted MOFs to be applied in the lithium-ion battery system. For the sake of ameliorate this issue, the Ni/NiO was well loaded on the surface of Cr-based metal organic frameworks (MIL-101) by solution impregnation and reduction method to form Ni/NiO@MIL-101(Cr) composites. The as-synthesized Ni/NiO@MIL-101(Cr) was characterized by X-ray powder diffractions, X-ray photoelectron spectroscopy, field emission scanning electron microscope and transmission electron microscope techniques. When used as anode for LIBs, the Ni/NiO@MIL-101(Cr) composite exhibited high reversible capacity (891 mAh g after 100 cycles at a current density of 200 mA g) and stable cycle performance, the coulombic efficiency can maintain in the whole cycle above 95.0%. The reasons for that Ni/NiO@MIL-101(Cr) behaved outstanding electrochemical properties were discussed also. The Ni/NiO@MIL-101(Cr) can be used as promising material for lithium-ion battery application.
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http://dx.doi.org/10.1166/jnn.2019.16763DOI Listing
December 2019

Visible light driven photoelectrochemical sensor for chromium(VI) by using BiOI microspheres decorated with metallic bismuth.

Mikrochim Acta 2019 05 11;186(6):345. Epub 2019 May 11.

Department of Environmental Sciences, Zhejiang Provincial Key Laboratory of Watershed Science and Health, Wenzhou Medical University, Wenzhou, 325035, People's Republic of China.

Composites were prepared from BiOI and Bi/BiOI-X (where x can be 1, 2, 3, or 4) by a one-step solvothermal method and used to design a photoelectrochemical (PEC) assay for chromium(VI). The chemical composition and morphology of the materials were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results of UV-vis DRS (Diffuse reflection spectra) and photoluminescence show the composites to have higher visible light absorption and a lower electron recombination rate compared to BiOI alone. Photogenerated electrons reduce hexavalent chromium to trivalent chromium, and the consumption of electrons cause noticeable enhances of the photocurrent density after the addition of Cr(VI). Thus, the Cr(VI) concentration can be measured by monitoring the increase of photocurrent density. The Bi/BiOI-3 material displays the best performance for detecting Cr(VI). The method has a wide linear range (1 to 230 μM) and a low detection limit of 0.3 μM (at S/N = 3). It is stable, selective, reproducible and was applied to the determination of nitrite in spiked tap water and lake water samples. Graphical abstract Schematic presentation of a electrochemical sensor based on Bi/BiOI for the determination of Cr(VI).
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http://dx.doi.org/10.1007/s00604-019-3463-0DOI Listing
May 2019

Cytotoxic and antibacterial polyketide-indole hybrids synthesized from indole-3-carbinol by .

Acta Pharm Sin B 2019 Mar 28;9(2):369-380. Epub 2018 Sep 28.

State Key Laboratory Cultivation Base for TCM Quality and Efficacy, Nanjing University of Chinese Medicine, Nanjing 210046, China.

Two skeletally undescribed polyketide-indole hybrids (PIHs), named indolchromins A and B, were generated from indole-3-carbinol (I3C) in the fungal culture (). The indolchromin structures were elucidated mainly by their 1D and 2D NMR spectra with the former confirmed by the single-crystal X-ray crystallographic analysis. Each indolchromin alkaloid was chirally separated into four isomers, whose absolute configurations were assigned by comparing the recorded circular dichroism (CD) spectra with the electronic CD (ECD) curves computed for all optional stereoisomers. Furthermore, the indolchromin construction pathways in fungal culture were clarified through enzyme inhibition, precursor feeding experiment, and energy calculation. The cascade reactions, including decarboxylative Claisen condensation catalyzed by 8-amino-7-oxononanoate synthase (AONS), C()-H activation, double bond migration, and Michael addition, all undergone compatibly during the fungal cultivation. In an MIC range of 1.3-8.6 μmol/L, (2,4)- and (2,4)-indolchromin A and (2,4)-indolchromin B are inhibitory against , , sp., , and . (2,4)-Indolchromin A and (2,4)-indolchromin B were cytotoxic against the human breast cancer cell line MDA-MB-231 with IC values of 27.9 and 131.2 nmol/L, respectively, with the former additionally active against another human breast cancer cell line MCF-7 (IC 94.4 nmol/L).
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http://dx.doi.org/10.1016/j.apsb.2018.09.011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6437554PMC
March 2019

NiN/NF as Bifunctional Catalysts for Both Hydrogen Generation and Urea Decomposition.

ACS Appl Mater Interfaces 2019 Apr 1;11(14):13168-13175. Epub 2019 Apr 1.

Institute for Sustainable Energy/College of Sciences , Shanghai University , Shanghai 200444 , China.

Oxygen evolution reaction (OER) has a high overpotential, which can significantly reduce the energy efficiency in water decomposition. Using urea oxidation reaction (UOR) to replace OER has been a feasible and energy-saving approach because of its lower electrode potential. Furthermore, UOR is also an important process in wastewater treatment. This paper successfully synthesizes a high-performance bifunctional catalyst for urea electrolysis. The catalyst is nickel nitride bead-like nanospheres array supported on Ni foam (NiN/NF). Several characterization methods are used to analyze the catalyst's morphology, structure, and composition as well as catalytic activity/stability, including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical methods (cyclic voltammetry, linear sweep voltammetry, electrochemical impedance spectroscopy, and CAM). A concurrent two-electrode electrolyzer (NiN/NF∥NiN/NF) is constructed and used to validate the catalyst performance, and the results show that the cell achieves 100 mA·cm at 1.42 V, while the cell voltage of Pt/C∥IrO is 1.60 V, indicating that the NiN/NF catalyst is superior to precious metals.
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http://dx.doi.org/10.1021/acsami.8b19052DOI Listing
April 2019

A nanocomposite consisting of gold nanobipyramids and multiwalled carbon nanotubes for amperometric nonenzymatic sensing of glucose and hydrogen peroxide.

Mikrochim Acta 2019 03 12;186(4):235. Epub 2019 Mar 12.

Department of Environmental Sciences, Zhejiang Provincial Key Laboratory of Watershed Science and Health, Wenzhou Medical University, Wenzhou, 325035, People's Republic of China.

Gold nanobipyramids were synthesized by a seed-mediated growth method and then supported by multi-walled carbon nanotubes (denoted as AuNBP/MWCNTs). The electrocatalytic activity of the AuNBP/MWCNTs on a glassy carbon electrode (GCE) towards direct glucose oxidation and hydrogen peroxide reduction was superior to that of AuNBPs and MWCNTs. The modified GCE, operated at a typical working voltage of +0.15 V (vs. SCE) and in 0.1 M NaOH solution, exhibits a linear response in the 10 μM to 36.7 mM glucose concentration range with a 3.0 μM detection limit (at S/N = 3) and a sensitivity of 101.2 μA mM cm. It also demonstrates good sensitivity towards hydrogen peroxide in at pH 7 solution at a working potential of -0.50 V (vs. SCE), with a linear response range from 5.0 μM to 47.3 mM, a sensitivity of 170.6 μA mM cm and a detection limit of 1.5 μM. Graphical abstract A electrochemical sensing platform based on the use of gold nanobipyramids and multi-walled carbon nanotubes nanocomposites (AuNBP/MWCNTs) is described for the determination of glucose and hydrogen peroxide.
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http://dx.doi.org/10.1007/s00604-019-3272-5DOI Listing
March 2019

Synthesis of CuO/g-CN composites, and their application to voltammetric sensing of glucose and dopamine.

Mikrochim Acta 2018 12 10;186(1):10. Epub 2018 Dec 10.

School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning, 437100, China.

The preparation of 3 kinds of carbonaceous nanocomposites by hydrothermal treatment and subsequent calcination described. The first comprises a nanomaterial of type CuO/g-CN, with g-CN in mass fractions of 2, 5 and 7 wt%, respectively. The second comprises CuO/porous carbon (5 wt%), and the third comprises CuO/carbon spheres (5 wt%). All of them were employed to modify a glassy carbon electrode (GCE) to obtain electrochemical sensors for glucose and dopamine. The GCE modified with CuO/g-CN (5 wt%) displays the highest electrocatalytic activity towards glucose and dopamine. Figures of merit for sensing glucose (in 0.1 M NaOH solution) include a wide linear range (0.5 μM to 8.5 mM), a detection limit of 0.150 μM, and a sensitivity of 0.274 μA·μM·cm (at a working potential of 0.60 V vs. Ag/AgCl). The respective data for dopamine (in pH 7.0 solution) are linear ranges from 0.2-16.0 μM and 16.0-78.7 μM, a lower detection limit of 60 nM, and an electrochemical sensitivity of 0.834 and 0.331 μA·μM·cm (at a working potential of 0.22 V vs. Ag/AgCl). The good performance of the modified GCE is attributed to the synergetic interactions between CuO and the appropriate fraction of g-CN, and the improvement of conductivity. Graphical abstract Schematic presentation of a electrochemical sensor based on CuO/g-CN for the determination of glucose and dopamine.
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http://dx.doi.org/10.1007/s00604-018-3120-zDOI Listing
December 2018

Synthesis of C-C Bonded Two-Dimensional Conjugated Covalent Organic Framework Films by Suzuki Polymerization on a Liquid-Liquid Interface.

Angew Chem Int Ed Engl 2019 Jan 2;58(5):1376-1381. Epub 2019 Jan 2.

Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Hubei Key Laboratory of Polymer Materials & College of Chemistry and Chemical Engineering, Hubei University, Wuhan, 430062, P. R. China.

Synthesis of free-standing two-dimensional (2D) conjugated covalent organic framework (COF) films linked by C-C bonds is highly desirable. Now a very simple and mild strategy has been developed to synthesize them by Suzuki polymerization on a water-toluene interface in a refrigerator. The versatility of this strategy was confirmed by the successful synthesis of two different 2D-COF films: a porous graphene and a porphyrin-contained 2D-COF. Both 2D-COF films have large lateral size and their crystalline domains were visualized by high resolution TEM. Based on the wide compatibility of Suzuki reaction, our breakthrough work opened a door for the synthesis of various 2D conjugated COF films. For application studies, the porous graphene exhibits a good carrier mobility, which is much higher than -C=N- linked 2D COF films and a good catalytic activity for hydrogen evolution reaction, which is comparable with nitrogen- or phosphorus-doped graphene.
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http://dx.doi.org/10.1002/anie.201811399DOI Listing
January 2019

Neural bases underlying the association between balanced time perspective and trait anxiety.

Behav Brain Res 2019 02 5;359:206-214. Epub 2018 Nov 5.

The Lab of Mental Health and Social Adaptation, Faculty of Psychology, Southwest University, Chongqing, China; Research Center of Mental Health Education, Southwest University, Chongqing, China. Electronic address:

The aims of present study were to investigate the association between balanced time perspective (BTP) and trait anxiety, and the neural substrates underlying this association using voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) methods. 140 college students (83 females) ranging in age from 17 to 25 years were assessed on deviation from the balanced time perspective (DBTP) and trait anxiety. Behavioral analyses found BTP could significantly predict trait anxiety after controlling age and gender. Whole-brain VBM analyses found that DBTP was positively correlated with gray matter volume (GMV) in the parahippocampal gyrus (PHG) and precuneus, while trait anxiety positively correlated with GMV in the PHG. Considering the overlapping region in the PHG, we further defined the overlapping region as the seed, and calculated seed-to-voxel-based functional connectivity in resting-state. RSFC results showed that DBTP was positively associated with the RSFC between the PHG and medial prefrontal cortex (mPFC), posterior cingulate cortex (PCC), and precuneus, whereas negatively correlated with the RSFC between the PHG and cuneus. Trait anxiety was also positively correlated with the RSFC between the PHG and PCC while negatively correlated with the RSFC between the PHG and cuneus. Mediation analysis further found GMV in the overlapping PHG and PHG-PCC, PHG-cuneus functional connectivity played significantly mediating roles in the relation between DBTP and trait anxiety. In sum, our research suggests the structural features of the PHG and its connectivity with PCC and cuneus may be the neural bases underlying the association between BTP and trait anxiety.
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http://dx.doi.org/10.1016/j.bbr.2018.10.039DOI Listing
February 2019

Novel Cobalt-Doped NiSe Chalcogenides (Co NiSe) as High Active and Stable Electrocatalysts for Hydrogen Evolution Reaction in Electrolysis Water Splitting.

ACS Appl Mater Interfaces 2018 Nov 13;10(47):40491-40499. Epub 2018 Nov 13.

Energy, Mining and Environment , National Research Council of Canada , Vancouver , British Columbia V6T1W5 , Canada.

In this paper, novel cobalt-doped NiSe chalcogenides (Co NiSe, x = 0.05, 0.1, 0.2, 0.3, and 0.4) are successfully synthesized and studied as high active and stable electrocatalysts for hydrogen evolution reaction (HER) in electrolysis water splitting. The morphologies, structures, and composition of these as-prepared catalysts are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, and transmission electron microscopy. The electrochemical tests, such as linear sweep voltammetry, cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry testing, are performed to evaluate these catalysts' HER catalytic performance including activity and stability. The results indicate that a suitable doping can result in synergetic effect for increasing the catalytic performance. Among different catalysts, CoNiSe shows the highest HER performance. After introducing the reduced graphene oxide (rGO) into this catalyst as the support, the resulted CoNiSe/rGO shows even better performance than unsupported CoNiSe, which are confirmed by the reduction of HER overpotential of CoNiSe/rGO to 103 mV compared to 153 mV of CoNiSe at a current density of 10 mA/cm, and the smaller Tafel slope (43 mV/dec) and kinetic resistance (21.34 Ω) than those of CoNiSe (47 mV/dec, 30.23 Ω). Furthermore, the large electrochemical active surface area and high conductivity of such a CoNiSe/rGO catalyst, induced by rGO introduction, are confirmed to be responsible for the high HER performance.
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http://dx.doi.org/10.1021/acsami.8b12797DOI Listing
November 2018

Radix flavone exhibits antitumor activity in colorectal cancer via Wnt/β-catenin signaling pathway.

Onco Targets Ther 2018 4;11:6437-6446. Epub 2018 Oct 4.

Department of Gastroenterology and Hepatology, Jinling Hospital, Medical School of Nanjing University, Nanjing, China,

Background: Radix flavone (RTHF) is extracted from a traditional Chinese medicinal herb , which is conventionally used as a folk medicine for its anti-inflammation activity and antiviral activity. In this study, the effects of RTHF on inhibiting malignant biological properties in colorectal cancer (CRC) were evaluated by conducting both in vitro and in vivo experiments, and the underlying mechanism was investigated.

Materials And Methods: Cell Counting Kit-8, colony formation, and flow cytometry assays were performed to evaluate the proliferation of RTHF-treated colon tumor cells. Migration and invasion capacities were also tested by cell wound scratch assay and Transwell invasion assay. Moreover, the antitumor effects of RTHF on azoxymethane/dextran sulfate sodium-induced colitis-related CRC were investigated in C57BL/6 mice. In addition, Western blot and/or quantitative reverse transcription polymerase chain reaction analysis were used to evaluate the expressions of Lgr5, Cyclin D1, c-Myc, and E-cadherin.

Results: These experiments showed that RTHF could decrease the cell growth kinetics and clone-forming capacity. RTHF could also dose dependently induce cell cycle arrest at G0/G1 phase and inhibit epithelial-mesenchymal transition process. Furthermore, downregulation of β-catenin activation and downstream protein expression were detected in CRC cells after being treated with RTHF. RTHF daily gavage suppressed the number and size of CRC in mice and inhibited Lgr5 and Cyclin D1 expressions in tumor tissue.

Conclusion: In conclusion, RTHF treatment inhibits colorectal tumor growth, decreases Wnt/β-catenin pathway activity, and downregulates target genes' expression.
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http://dx.doi.org/10.2147/OTT.S172048DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6177378PMC
October 2018

Synthesis of PbS and Ag2S Nanorods via Polyol Process.

J Nanosci Nanotechnol 2018 Aug;18(8):5831-5836

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials and Ministry of Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules, Hubei University, Wuhan 430062, China.

PbS and Ag2S nanorods have been synthesized using a polyol process in the presence of poly(vinylpyrrolidone) (PVP). First, the production of Pb or Ag was realized via the thermal decomposition of a lead/silver salt. Then the Pb or Ag precursor was directly combined with S power under heating, leading to the formation of the final products. The samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). PbS cubes and cubes with a hole in the center were prepared under different reaction conditions. Possible formation mechanisms of different PbS or Ag2S morphologies have briefly been discussed.
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http://dx.doi.org/10.1166/jnn.2018.15443DOI Listing
August 2018

Synthesis and Electrochemical Performance of NiCO₂S₄ as Anode for Lithium-Ion Batteries.

J Nanosci Nanotechnol 2018 Aug;18(8):5749-5755

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for the Synthesis and Applications of Organic Functional Molecules, Hubei University, Wuhan 430062, China.

NiCO2S4 with different morphology was controllably fabricated by a facile hydrothermal and solvothermal route. The as-obtained samples were analyzed and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The results reveal that the sample (NCS-1) prepared by hydrothermal method manifest a mixture of nanorods and nanospheres. The sample (NCS-2) synthesized by solvothermal process takes on spherical nanoparticles (NPs). It is found that the morphology of the sample has much influence on the electrochemical property. When applied as anode for lithium-ion batteries (LIBs), the NiCO2S4 NPs (NCS-2) possess the highest reversible discharge capacity of 1469.8 mAh g-1 compared with other two samples at the current density of 100 mA g-1 in the voltage window of 0.01-3 V. Additionally, it remains a specific capacity of 1163.7 mAh g-1 at a current density of 100 mAg-1 after 100 cycles. This excellent electrochemical performance arises from its unique mesoporous structure, which can reduce the transport lengths of both lithium ions and electrons. The mesoporous NiCO2S4 NPs show the great potential development of high-capacity anode materials for LIBs.
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http://dx.doi.org/10.1166/jnn.2018.15468DOI Listing
August 2018

Controlled Preparation of Co9S8 for Small Molecule Sensing Platform.

J Nanosci Nanotechnol 2018 Aug;18(8):5582-5590

The Chinese People's Armed Police Forces Academy, Langfang 065000, China.

Cobalt sulfides with different atomic ratios were synthesized by two different methods. Electrochemical testing was used to compare the prepared cobalt sulfides samples, and a series of physical characterizations was carried out. The results demonstrated that the better materials had the phase of Co9S8. Furthermore, the pompon-like Co9S8 had a larger specific surface area (45.46 m2 g-1), which offered more active sites for the detection of hydrogen peroxide and glucose. The sensor based on pompon-like Co9S8 displayed a wide linear response ranged from 1.50 μM to 8.51 mM, a favorable sensitivity of 20.80 μA mM-1 cm-2 and a detection limit of 0.45 μM (signal to noise ratio of 3) for hydrogen peroxide. Additionally, the sensor also had a linear response ranged from 21.50 μM to 1.18 mM, and a higher sensitivity of 185.32 μA mM-1 cm-2 for glucose. The sensors also exhibited excellent performances in selectivity, stability, and reproducibility.
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http://dx.doi.org/10.1166/jnn.2018.15389DOI Listing
August 2018

Immobilization of Enzymes on a Phospholipid Bionically Modified Polysulfone Gradient-Pore Membrane for the Enhanced Performance of Enzymatic Membrane Bioreactors.

Molecules 2018 Jan 11;23(1). Epub 2018 Jan 11.

MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.

Enzymatic membrane bioreactors (EMBRs), with synergistic catalysis-separation performance, have increasingly been used for practical applications. Generally, the membrane properties, particularly the pore structures and interface interactions, have a significant impact on the catalytic efficiency of the EMBR. Therefore, a biomimetic interface based on a phospholipid assembled onto a polysulfone hollow-fiber membrane with perfect radial gradient pores (RGM-PSF) has been prepared in this work to construct a highly efficient and stable EMBR. On account of the special pore structure of the RGM-PSF with the apertures decreasing gradually from the inner side to the outer side, the enzyme molecules could be evenly distributed on the three-dimensional skeleton of the membrane. In addition, the supported phospholipid layer in the membrane, prepared by physical adsorption, was used for the immobilization of the enzymes, which provides sufficient linkage to prevent the enzymes from leaching but also accommodates as many enzyme molecules as possible to retain high bioactivity. The properties of the EMBR were studied by using lipase from for the hydrolysis of glycerol triacetate as a model. Energy-dispersive X-ray and circular dichroism spectroscopy were employed to observe the effect of lecithin on the membrane and structure changes in the enzyme, respectively. The operational conditions were investigated to optimize the performance of the EMBR by testing substrate concentrations from 0.05 to 0.25 M, membrane fluxes from 25.5 to 350.0 L·m·h, and temperatures from 15 to 55 °C. As a result, the obtained EMBR showed a desirable performance with 42% improved enzymatic activity and 78% improved catalytic efficiency relative to the unmodified membrane.
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http://dx.doi.org/10.3390/molecules23010144DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6017099PMC
January 2018